磁化微咸水对南疆盐渍土壤水分入渗及盐分淋出特征的影响

Effects of Magnetized Brackish Water on Soil Water Infiltration and Salt Leaching Characteristics of Saline Soil in Southern Xinjiang

为探究磁化微咸水灌溉对南疆盐渍土入渗及盐分离子迁移特征的影响,采用恒定磁场强度400 mT对矿化度分别为0、2、3、5 g/L微咸水进行磁化处理,以未磁化处理为对照,对比分析各处理累积入渗量、湿润锋运移距离和淋洗后不同土壤剖面总盐、脱盐率、盐分离子和SAR的影响规律。结果表明:磁化微咸水入渗减小了相同时间内的累积入渗量和湿润锋深度,降低了Philip入渗模型吸渗率,土壤含水率比未磁化微咸水提高5.00%~6.29%;磁化处理显著降低了土壤含盐量,对0~50 cm土壤内总盐含量磁化处理较未磁化降低11.79%~41.64%,在同一磁化强度下,土壤含盐量随矿化度的增加而增加,脱盐率随矿化度的增加而降低。在同一矿化度下,磁化处理含盐量低于未磁化处理,脱盐率高于未磁化处理。磁化微咸水灌溉有利于降低土壤中盐分离子含量,0~50 cm土层K^(+)、Na^(+)、Ca^(2+)、Mg^(2+)、HCO_(3)^(-)、Cl^(-)、SO_(4)^(2-)含量磁化较未磁化处理降低16.90%~25.97%、43.62%~64.68%、11.15%~31.44%、-8.12%~49.07%、-74.14%~13.43%、21.46%~52.81%、6.66%~13.10%。磁化微咸水灌溉处理显著降低0~50 cm土层深度处土壤SAR。

To explore the effect of magnetized brackish water irrigation on the infiltration and salt ion migration characteristics of saline soil in southern Xinjiang,the constant magnetic field intensity of 400 mT was used to magnetize the brackish water with salinity of 0,2,3 and 5 g/L,respectively.An unmagnetized treatment was used as the control.We compared and analyzed the effects of cumulative infiltration,wetting front migration distance and total salt,desalination rate,salt ions and SAR in different soil profiles after leaching.The results showed that:The infiltration of magnetized brackish water reduced the cumulative infiltration and wetting front depth in the same time.Also,it reduced the infiltration rate of Philip infiltration model.The soil water content was 5.00%~6.29%higher than that of unmagnetized brackish water.The magnetized brackish water irrigation treatment significantly reduced the soil salt content,and the total salt content in the 0~50 cm soil was 11.79%~41.64%lower than that of the unmagnetized treatment.Under the same magnetization intensity,the soil salt content increased with the increase of salinity,and the desalination rate decreased with the increase of salinity.Under the same salinity,the salt content of magnetization treatment is lower than that of non-magnetization treatment,and the desalination rate is higher than that of non-magnetization treatment.Magnetized brackish water irrigation was beneficial to reduce the content of salt ion in soil.The contents of K^(+),Na^(+),Ca^(2+),Mg^(2+),HCO_(3)^(-),Cl^(-)and SO_(4)^(2-)in 0~50 cm soil layer were 16.90%~25.97%,43.62%~64.68%,11.15%~31.44%,-8.12%~49.07%,-74.14%~13.43%,21.46%~52.81%and 6.66%~13.10%lower than those in unmagnetized treatment.Magnetized brackish water irrigation treatment significantly reduced soil SAR at 0~50 cm soil depth.